Virtual Extensible Local Area Network (VxLAN) is a technology in which a layer 2 packet is encapsulated by using a layer 3 protocol. According to a main technical principle of VxLAN, an encapsulated packet in a media access control in user datagram protocol (MAC-in-UDP) format is introduced, that is, an Ethernet frame is encapsulated in a User Datagram Protocol (UDP) packet for transmission, to transmit the Ethernet frame on a layer 3 network. In this way, a layer 2 network is extensible within a layer 3 range. In a service scenario in which a data center (DC) intercommunicates with a virtual network of a site, the DC provides virtual machine (VM) services for multiple enterprises, and a host of the site communicates with a VM in the DC through a VxLAN tunnel. In implementation, a DC-side provider edge (PE) device needs to create a corresponding sub-interface for each tenant, and each sub-interface is bound to a corresponding virtual private network (VPN) routing and forwarding (VRF) table, thereby implementing interconnection between a DC-side network and a provider network.
However, in an actual application, a sub-interface on the DC-side PE device needs to be allocated to each VRF, and then the allocated sub-interface is bound to a corresponding VRF. Therefore, there is the following problem. Because a new sub-interface needs to be allocated on the DC-side PE device when a new tenant is added, relatively many interface resources on the DC-side PE device are occupied, and a corresponding configuration process is complex.